COMPOSITAE 651 



3 Syrphidae. Loew noticed the butterfly Pieris brassicae L., skg., in the Berhn 

 Botanic Garden. 



I535- C. glabnim DC. (=Cnicus spinosissimus Z. (?)).— The heads of this 

 species are yellowish-white in colour. 



Visitors. — MacLeod (PjTenees) saw the humble-bee Bombus hortorum Z. $ 

 (Bot. Jaarb. Dodonaea, Ghent, iii, 1891, p. 352). 



1536. C. semilatum Bieb. (=Cnicus serrulatus Bieb). — 



Visitors. — Loew observed the following in the Berlin Botanic Garden. — 



A. Hymenoptera. (a) Apidae : i . Psithyrus rupestris F. S, skg. (b) Sphegidae : 

 2. Ammophila sabulosa Z. B. Lepidoptera. Rhopalocera: 3. Rhodocera rhamni 

 Z., skg. ; 4. Pieris brassicae Z., do. : and on the var. ucranicum Bess., 2 bees 

 (Psithyrus campestris Pz. $, skg. ; and P. vestalis Fourcr. t). 



467. Kentrophyllum Neck. 



1537. K. lanatum DC. et Duby (=Carthamus lanatus Z.). — 

 Visitors. — Schletterer observed the rare bee Halictus quadrinotatus K. 



468. Silybum Vaill. 



Stylar branches covered externally by short sweeping-hairs, a ring of longer, 

 usually somewhat oblique ones, at their base. They diverge only at the tip, during 

 the second stage of anthesis. 



1538. S. Marianum Gaertn. ( = Carduus Marianus Z.). (Sprengel, ' Entd. Geh.,' 

 pp. 371-2.) — The florets of this species are purple-red in colour. Hildebrand states 

 that the pollen-grains are sometimes imperfect in heads that mature early (U. d. 

 Geschlechtsverhalt. b. d. Compositen,' pp. 60-2). — 



Visitors. — Buddeberg saw the following bees in Nassau (Herm. Miiller, ' Weit. 

 Beob.,' Ill, p. 81).— 



I. Chelostoma nigricorne Nyl. 5, skg.; 2. Halictus sexcinctus F. }, skg. and 

 po-cltg. ; 3. H. tetrazonius Klg. 5, skg. ; 4. Megachile fasciata Sm. S, skg. ; 

 5. Osmia adunca Pans. 5, do. ; 6. O. fulviventris Pz. 5, do. ; 7. Stelis phaeoptera 

 K. S, do. 



469. Carduus L. 



Florets tubular and hermaphrodite. Stylar branches diverge only at the tip ; 

 externally a ring of sweeping-hairs at their base ; margins of inner surfaces (which 

 appear at a later stage) beset with stigmatic papillae. 



1539. C. crispus L. (Herm. Muller, ' Fertilisation,' pp. 338-9, ' Weit. Beob.,' 

 in, p. 83; Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 95, 161; Heinsius, Bot. 

 Jaarb. Dodonaea, Ghent, iv, 1892 ; Loew, 'Blutenbiol. Floristik,' p. 395.) — Hermann 

 Muller says that in this species 35-80 bright purple florets are aggregated into a head 

 which is scarcely 10 mm. in diameter below, but they curve outwards in such a way 

 that a red surface 25-30 mm. across is presented above. The corolla of each floret 

 expands into a ventricose bell, 2A-3 mm. long, with linear slightly diverging lobes 

 4_5^ mm. in length. The flower mechanism agrees in other respects with that 

 of the hermaphrodite florets of Cirsium arvense, but, owing to the depth of the 



